ML20206U541

Non-proprietary Errata Pages for Rev 2,Addendum 1 to WCAP-13699, Laser Welded Sleeves for 3/4 Inch Diamete Tube Feedring Type & W Preheater SGs Generic Sleeving Rept

ML20206U541
Person / Time
Site:	South Texas
Issue date:	05/18/1999
From:	WESTINGHOUSE ELECTRIC COMPANY, DIV OF CBS CORP.
To:
Shared Package
ML20137Q103	List: ML20206U541 NOC-AE-000544, Forwards Errata Pages for Proprietary Rev 2,Addendum 1 to WCAP-13698 & non-proprietary Rev 2,Addendum 1 to WCAP-13699 Versions of Laser Welded Sleeves for 3/4 Inch Diameter Tube Feedring Type & W Preheater.... Proprietary Rept Withheld
References
WCAP-13699-ADD1, WCAP-13699-ADD1-ERR, NUDOCS 9905250250
Download: ML20206U541 (3)

Text

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NOC-AE-000544  ;

Attachment 2 Page 1 of 3 ATTACHMENT 2 Errata pages for WCAP-13699, Rev. 2, Addendum 1 Non-Proprietary 9905250250 990518 PDR P ADOCK 05000498 PDR

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.. r 8.8 Fatigue Analysis In the laser welded sleeve (LWS) repair of steam generator tubes, the Alloy 690 sleeve is hydraulically expanded against the host Alloy 600 tube and a laser inside the sleeve is used

- to autogenously fuse the Alloy 690 sleeve and Alloy 600 tube over the full 360*

circumference. The evaluation presented in this section demonstrates that the current minimum required laser weld axial engagement (fused) length of 0.015 inch satisfies the fatigue requirement of the ASME Code, Reference (1), with mspect to the specified generic cyclic loads given in Reference (2). The ASME Code fatigue requirement is given in Section 2.3. The evaluation considers the following sleeve types for installation in

' Westinghouse steam generators with 3/4 inch OD x 0.043 inch wall host tubes and ABB CE

. steam generators with 3/4 inch OD x 0.048 inch wall host tubes: l Full Length Tubesheet Sleeve (FLTS),

Elevated Tubesheet Sleeve (ETS), l l

Tube Support Plate Sleeve (TSS).

For each of the above sleeve types, the fatigue evaluation considers all possible

. combinations of(

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3.3.1 Geometry and Materials The weld is located at approximately the center of the 2.5 inch hydraulically expanded length of sleeve. The residual stresses due to the hydraulic expansion and the laser  ;

welding process are removed by heat treatment prior to returning the sleeved tube to service. Therefore, it is reasonable to assume that the strength properties (including the S N fatigue curves) of Alloy 690 in the ASME Code also apply to the weld.

. Geometry The fatigue evaluation of the laser weld considers the following sleeve types:

Full Length Tubesheet Sleeve (FLTS), 36 inch length, Elevated Tubesheet Sleeve (ETS),12 inch length, Tube Support Plata Sleeve (TSS),12 inch lengti, for 3/4 Westinghouse Host Tubes.

Tube Support Plate Sleeve (TSS),15 inch length for 3/4 ABB CE Host Tubes .

All hydraulic expansion lengths are assumed to be 2.5 inches with 0.95 inch long transitions at each end. Most geometric parameters are assumed to be at their nominal values, except that the minimum weld engagement length of 0.015 inch is assumed for all laser welds. The nominal o' uter diameter and wall thickness of the sleeve and tube are:

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' Westinghouse 3/4 Host Tube:- 0.750 inch OD x 0.043 inch' wall,

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m Sleeve: [' lae inch' wall. .

ABB CE 3/4 Host Tube: '0.750 inch OD x 0.048 inch wall, y

31eeve: [. ]ae inch wall.

Material Data .

~

The following material properties,'taken from the ASME Code ~, Reference (1), are used in

.the fatigue evaluation:

. .. . lAllov 600 Tubes at 550*F E = elastic modulus = 28.85x108 psi

' p = Poisson's ratio = 0.3 a = mean coefficient of thermal expansion from 70*F = 7.77x104 (*F) 1

. K = thermal conductivity =. 2.57x101 BTU / (sec in 'F)

' Allov 690 Sleeve at 600*F-E = elastic modulus = 27.8x108 psi-

p = Poisson's ratio = 0.3 a = mean coefficient of thermal expansion from 70*F = 8.16x104 (*F) 1

. K = thermal conductivity = 2.31x104 BTU / (sec in *F)-

SA 508 Class 2 or 2a Tubesheet at 600*F E = elastic modulus = 26.4x108 psi -  !

p = Poisson's ratio = 0.3  !

a = mean coefficient of thermal expansion from 70'F = 7.42x104 (*F) 1 Air et 600*F (ammumed in the ran between the unexoanded sleeve and host tube)  !

= K = thermal conductivity = 5.78x10 7 BTIJ / (sec in *F) I 3.3.2 ~ Cveh Load Conditions J

The~ cyclic loads used in this evaluntion are defined in the generic laser welded sleeve (LWS)

' design specification for the 3/4 inch OD host tubes, Reference (2). The normal, upset, and

' test transients am generally 'given in terms of transient thanges relative to an initial steady state condition, usually at full power operation. The full power conditions, which are assumed in the generic LWS fatigue evaluation, are listed below:

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